1. Field of the Invention
The invention relates to a method for manufacturing plastic containers for liquids. The container comprises four sidewalls, a bottom wall, and a top wall. A closable filling socket is provided in the top wall. A dispensing valve of plastic material, in particular, a butterfly valve or a ball valve, comprising a valve housing that has an intake socket and an outlet socket is provided. The intake socket of the valve housing is connected to a discharge opening for receiving the dispensing valve located in a lower recess of the front wall of the container.
2. Description of the Related Art
In a method disclosed in German patent application 102 37 808 A1 for manufacturing a plastic container for liquids with a dispensing valve configured as a butterfly valve and used as a pallet container, a dispensing socket that has been pre-manufactured as a plastic part by injection-molding and comprises an outer thread is introduced into the blow mold and is fused to the container when blow molding the liquid container. After removal of the cooled container from the mold, a cutting tool is inserted into the dispensing socket and a discharge opening is cut out of the container wall with the cutting tool. Subsequently, the dispensing valve is screwed by means of a union nut onto the dispensing socket of the liquid container.
According to another known method for manufacturing plastic containers for liquids with a dispensing valve, the intake socket of the valve housing that is pre-manufactured as a plastic part by injection-molding and inserted into the blow mold is fused to the container when blow-molding the container. After removal of the cooled container from the mold, a discharge opening is cut out of the container-wall by a cutting tool inserted into the valve housing. Subsequently, the closure member and the actuating shaft with the actuating lever are mounted in the valve housing.
According to the two known manufacturing methods, the insertion of the dispensing socket or of the valve housing into the blow mold prolongs the blow-molding cycle; therefore, the production output of the manufacturing facility is reduced. In the second manufacturing process, the assembly steps required for completion of the dispensing valve after blow-molding of the plastic container for liquids additionally reduces the production output of the manufacturing facility.